Table 2. Characteristics of Research Participantsa.
| Age (years) | 25.122±10.32 |
| Sex (no. of male/female) | 37/28 |
| Tobacco use (no. of smokers) | 29 |
| Days used in the last 30 days | 17.57±2.87 |
| Alcohol use | |
| Days used in the last 30 days | 1.46±0.26 |
| Marijuana use | |
| Days used in the last 30 days | 0.33±0.12 |
| Ethnicity | |
| Caucasian | 26 |
| African American | 6 |
| Hispanic | 17 |
| Asian | 15 |
| American Indian | 1 |
Where appropriate, data are shown as means±SEM.